1. Field of the Invention
The invention relates to surgical implants, and is directed more particularly to the making of such implants having relatively rigid plate portions and pliable, textured, mesh portions, either portion being provided with at least one screw hole to facilitate attachment to bone.
2. Description of the Prior Art
The use of surgical implants is well known. Surgically implantable metal devices generally are formed of plates or sheets of inert metal, such as titanium, compatible with human and animal tissue. When such implants are positioned between bone and soft tissue, a textured, roughened traction surface in contact with the bone promotes ingrowth of the bone, bonding with the traction surface and enhancing the permanent, stable positioning of the implant. Textured bone-contacting surfaces thus enhance the stability of the metal implants after surgery. The desirablility of rough, textured, bone-engaging surfaces to assure stable positioning of surgical implants has been recognized and has been discussed in U.S. Pat. No. 5,258,098, issued Nov. 2, 1993, in the names of Donald J. Wagner et al, U.S. Pat. No. 5,298,115, issued Mar. 29, 1994, in the name of Ian Leonard, U.S. Pat. No., 5,456,723, issued Oct. 10, 1995, in the names of Samuel G. Steinemann et al, U.S. Pat. No. 5,507,815, issued Apr. 16, 1996, in the names of Donald J. Wagner et al, U.S. Pat. No. 5,603,338, issued Feb. 18, 1997, in the name of Keith D. Beaty, U.S. Pat. No., 5,853,561, issued Dec. 29, 1998, in the name of Bruce A. Banks, U.S. Pat. No. 5,922,029, issued Jul. 13, 1999, in the names of Donald J. Wagner et al, and U.S. Pat. No. 5,965,006, issued Oct. 12, 1999, in the names of Roland Baege et al.
Some implants are formed as thin mesh sheets, of extremely light weight and with numerous openings therethrough. In some cases, bendable mesh implants require relatively stiff, unbendable reinforcing plate portions. The formation of perforated thin metallic sheets, or plates, is described in several U.S. patents, including U.S. Pat. No. 3,359,192, issued Dec. 19, 1967, in the names of Hans-Joachim Heinrich et al, U.S. Pat. No. 5,606,589, issued Feb. 25, 1997, in the names of Anthony J. Pellegrino et al, and U.S. Pat. No. 5,814,235, issued Sep. 29, 1998, in the names of Anthony J. Pellegrino et al. Through-holes penetrating such plate portions are useful for receiving mounting screws, anchoring the mesh-and plate implant in position. However, the manufacture of such implants combining a relatively thin pliable sheet with a thicker unbendable plate, and with mounting screw holes therein, has presented some challenges still lacking feasible and economical solutions.
An object of the invention is, therefore, to provide a method for making a mesh-and-plate surgical implant including bendable perforated mesh portions adjoining stiff, rigid reinforcing plate portions.
A further object is to provide a method for making such implants having therein mounting screw holes which pass therethrough, for receiving mounting screws installed during implantation.
With the above and other objects in view, a feature of the present invention is the provision of a method for making a mesh-and-plate surgical implant, the method comprising the steps of applying maskant to first and second faces of a metal sheet, selectively ablating the maskant on both faces, affixing a first protective tape to the first face to cover same and maskant thereon, but leaving exposed a portion for a screw hole, affixing a second protective tape to the second face to cover same and maskant thereon, etching the first face screw hole portion to form a crater, removing the first tape, etching the crater and other exposed portions of the first face, removing the second tape, etching opposite the crater and other exposed portions of the second face to provide an opening in communication with the crater, and to provide other second face openings extending to the first face, and removing remaining maskant to provide the implant configured to include a pliable mesh portion and a rigid plate portion, and having screw holes therein.
The above and other features of the invention, including various novel details of construction and combinations of method steps, will now be more particularly described with reference to the accompanying drawings and pointed out in the claims. It will be understood that the particular method embodying the invention is shown and described by way of illustration only and not as a limitation of the invention. The principles and features of this invention may be employed in various and numerous embodiments without departing from the scope of the invention.